Method of heating ship walls and a device for carrying out the method



June 4, 1963 A. JoNssoN 3,092,066

METHOD OF HEATING SHIP WALLS AND A DEVICE FOR CARRYING OUT THE. METHOD Filed Jan. 30, 1961 3 Sheets-Sheet 1 olololo 3 ololOI DUDE] I INVENTOF? ALFRED abussoN TORN EVS June 4, 1963 A. JC'JNSSON 3,092,066

METHOD OF HEATING SHIP WALLS AND A DEVICE FOR CARRYING OUT THE METHOD Filed Jan. 50, 1961 s Sheets-Sheet 2 lmgemoR ALFRED 3614 550M ATTORNEYS June 4, 1963 Filed Jan. 30, 1961 FIG.9

A JNssou METHOD OF HEATING SHIP WALLS AND A DEVICE FOR CARRYING OUT THE METHOD 3 Sheets-Sheet '5 INVENTOR A LFRED JON SSON ATTORN EYS States Unite It is now considered more and more important to protect all parts of a ship against corrosion to the largest possible extent. This is mainly done by surfacing involving the use of oil, wax and tar mixtures or by painting with different kinds of paints. For a good result of such surfacing the surfaces to be treated must be entirely dry and in respect of certain lacquers they must also hold a certain minimum temperature which will normally lie at about 15 to 20 C.

One has experienced great difficulties in attempting to meet the above-mentioned requirements where ships are concerned which lie partly immersed in water. This particularly applies to the ship compartments which are intended for loads of oil and/ or ballast. For drying these compartments use is made of forced ventilation, sometimes in connection with heat within the compartments. This method, however, leads to an unsatisfactory result during a great part of the year when the water is colder than the air or the air has a high relative moisture content. In these cases moisture condenses on the colder surfaces, and the desired result cannot therefore be obtained.

The method according to the present invention eliminates the above-mentioned drawbacks. It relates to the heating of the inner side preferably of the ship walls which have their outer side in the water, and is particularly intended for use in connection with a surfacing of the inner side of the hull. The essential characteristic feature of the method is that the walls are treated in such a way on their outer side with a heating medium warmer than the surrounding water that heat is transmitted from said heating medium through the walls to the inner side thereof.

The invention is also directed to a device for carrying out the above method, and the characteristic features of said device reside in that it comprises a screening device which is adapted to be mounted around the ship so as to extend down into the water and to screen the water under the entire ship or part thereof from the water outside the screening device, and a heating device insertable between the screening device and the hull for heating the water within the screening device.

For a better understanding the invention will be described more in detail in the following, reference being made to the accompanying drawings, which illustrate some forms, chosen by way of example, of the device according to the invention, mounted to a ship. In the drawlngs:

FIG. 1 is a side elevational view of a ship with one form of the device according to the invention mounted in position around it;

FIG. 2 is a plan view of the showing of FIG. 1;

FIG. 3 is a cross section of the showing of FIG. 1, on a larger scale;

FIG. 4 is a View as seen from below of the device according to the invention in the first form thereof and on the same scale as in FIG. 3;

FIG. 5 is a side elevational view of part of a ship with a second form of the device mounted in position around it;

FIG. 6 is a plan view of the device shown in FIG. 5;

FIG. 7 is a cross section of a ship with a third form of atent the device according to the invention mounted in a position around it;

FIG. 8 is a cross section on line VIIIVIII in FIG. 7, on a larger scale;

FIG. 9 is a plan view of part of the device shown in FIG. 8.

In the drawings, 1 designates the schematically drawn ship with the screening device 2 mounted in position, extending down into the water and screening the water under the ship 1 from the water outside the screening device 2. Inserted between the screening device 2 and the ship 1 is a heating device 3 for heating the water inside the screening device to produce a layer of warm water adjacent the ship I.

In a preferred form of the invention the Water within the screening device 2 is heated by means of warm water which is caused to flow, preferably in the shape of spray jets, to the space inside the screening device 2. It is important that the warm water is not supplied more rapidly than the ships bottom is capable of transmitting the heat to the inside of the bottom, and that the temperature there will have the intended value, i.e. about 20 C. In this form of the invention the heating device 3 therefore consists of a pipe system 4 for the supply of warm water, the pipes in said system 4 being provided with upwardly directed perforations. Through these perforations the warm water is permitted to escape slowly so that the warm water impinges on the bottom plates which the pipes should engage. To realize such engagement the heating device 3 may be equipped with float means 5, preferably rubber bladders to be inflated with air.

The heating elements or pipe systems 4 can also be supported and held in position by ropes secured to the gunwale 6 in an obvious manner not shown.

In the preferred form the screening device 2 is a closed web of tarpaulin-canvas or like yielding material which is adapted to surround the entire ship 1 horizontally while extending vertically downwards. The screening device 2, which can thus be termed a skirt, extends from about 0.5 metre above the water surface 7 to about 2 metres below the bottom of the ship 1. The screening device 2 is preferably hung by means of ropes 8 or the like to the gunwale 6 of the ship 1. The tarpaulin screening device 2 is provided at its lower edge with sufficiently heavy sinkers 9 so that the tarpaulin will hang at least substantially vertically. I

In cases where only part of the ship 1 is to be heated, the screening device 2 is adapted to surround merely such part of the ship. The screening device 2 thenhas its upper edge provided with fioatmeans 1 0 for causing the device snugly to engage the ships bottom, as will appear from FIGS. Sand 6. The float means 10 may consist of a rubber hose of such a size that when filled with air it will carry the tarpaulin, pressing its upper edge against the ships bottom. The heating device 3 should consist in this instance of a plurality of sections, whereby the use of one or more of said sections is permitted, according to the necessity of the case.

Some parts of screening device 2 can be carried by ropes 8 while other parts are carried by float means 10'. The latter mainly applies to athwartship portions.

With the use of the screening device 2 the heat exchange takes place under insignificant or no loss of heat. The only loss of heat takes place at the edges of the relatively thin, heated water layer by its con-tact with the screening device 2 separating the warm water from the cold. This loss may be eliminated practically entirely by providing the screening device 2 with an insulating layer in the contact Zone. The screening device 2 also entails the advantage that the warm water layer is protected against disturbances caused by currents and waves.

In the form shown in FIGS. 7-9 the screening device 2 is composed of two superimposed tarpaulin canvases 11 and 12. The warm water 14 intended for the heating is to be kept between the ships wall 13 and the screening device 2 composed of the two canvases 11 and 12, while the cold Water is outside of the screening device 2. The spaces between the canvases 11 and 12 contain air for realizing a good heat insulation.

As' will appear from FIG. 8 the canvas 12 facing the ships wall 13 is adapted to form successive waves while the other canvas 11 is plane. The wave ridges shall engage the ships Wall 13 so that the volume of warm wateris kept at a minimum. Inserted in the space between each wave and the canvas 11 is a rubber hose which safely fills out the space 15 between the canvases 11 and 12 with air. In order that the length of the screening device 2 shall be kept unchanged in spite of the inflation etc. the device is equipped with longitudinal spring steel bars 16 secured to the canvases 11 and 12.

Disposed in each wave trough is a line 17 of rubber through which warm water is supplied. The lines 17 are preferably provided with longitudinal rows of small holes through which the warm water is permitted to flow in the form of spray jets into the space inside the screening device.

As will appear from FIG. 7, the web-like screening device 2 composed of the canvases 11 and 12 is equipped with means such as ropes 8 for its fixation to for instance the gunwale 6. As will appear from FIG. 9, the screening device 2 has holes in which said ropes 8 are secured to the device.

The lines 17 are of course connected to a central heating plant for warm water or steam while the rubber hoses 20 have couplings for connection to a source of compresed air.

All forms within the scope of this specification and/ or the appended claims are comprehended within the scope and spirit of this invention. All variations'and modifications of the invention are understood as being included the scope thereof.

What I claim and desire to secure by Letters Patent is:

1. A device for heating the walls of a ships hull comprising a screening device adapted to be positioned around the ship and spaced from the sides thereof and adapted to extend down into the water below the level of the bottom of the ship and screening the water under at least a part of the ship from the water outside the screening device, and a heating device insertable between the screening device and the ships hull for heating the water within the screening device.

2. A device as claimed in claim 1 in which the screening device is a closed web of tarpaulin-canvas like yielding material which is adapted to extend along at least a part of the ship horizontally while extend-ing vertically downwards.

3. A device as claimed in claim 2 in which the screening device is adapted to surround the entire ship, the screening device having ropes extending upwardly from its upper edges whereby the screening is adapted to be supported by ropes suspended from the gunwale of the ship.

4. A device as claimed in claim 2. in which the screening device is adapted to surround only part of the ship, the screening device having float means along the upper edge for causing the screening device snugly to engage the ships bottom.

5. A device as claimed in claim 2 in which the screening device has sinkers on its lower edge.

6. A device as claimed in claim 2 in which the heating device insertable between the screening device and the ships hull is a pipe system for supplying warm Water, the pipes in said system having upwardly directed perforations therein.

7. A device as claimed in claim 2 in which the heating device insertable between the screening device and the ships hull is constituted by one or more heating elements.

8. A device as claimed in claim 2 in which the heating device insertable between the screening device and the ships hull has float means thereon adapted to hold the heating device engaged with the ships bottom.

9. A device as claimed in claim 2 in which the screening device is a web comprising two superimposed tarpaulin canvases spaced from each other along at least a portion of their length, said web being adapted to engage the ships wall at spaced points with wanm water between the ships wall and said web and said web having air contained in the spaces between the tarpanlin canvases.

10. A device as claimed in claim 9 in which the tarpaulin canvas adapted to face the ships wall has a plurality of successive waves therein while the other tarpaulin canvas is flat.

11. A device as claimed in claim 10 in which an inflatable rubber hose is disposed in the space between each wave and the flat tarpaulin canvas.

12. A device as claimed in claim 10 in which the web has longitudinal spring steel bars secured thereto.

13. A device as claimed in claim 10 in which a supply line of rubber is provided in each wave trough for supplying warm water to the space between the web and the ship.

References Cited in the file of this patent UNITED STATES PATENTS 1,469,796 Lake Oct. 9; 1923 2,105,014 Segel Jan. 11, 1938 2,240,567 Meacha-m et a1 May 6, 1941 FOREIGN PATENTS 317,333 Germany Dec. 15, 1919 

1. A DEVICE FOR HEATING THE WALLS OF A SHIP''S HULL COMPRISING A SCREENING DEVICE ADAPTED TO BE POSITIONED AROUND THE SHIP AND SPACED FROM THE SIDES THEREOF AND ADAPTED TO EXTEND DOWN INTO THE WATER BELOW THE LEVEL OF THE BOTTOM OF THE SHIP AND SCREENING THE WATER UNDER AT LEAST A PART OF THE SHIP FROM THE WATER OUTSIDE THE SCREENING DEVICE, AND A HEATING DEVICE INSERTABLE BETWEEN THE SCREENING DEVICE AND THE SHIP''S HULL FOR HEATING THE WATER WITHIN THE SCREENING DEVICE. 